1. Field of the Invention
The present invention relates to a data management method and a data management apparatus for databases and files which deal with image, voice and various data.
2. Description of the Related Art
Conventionally, personal computers and work stations manage various types of files represented by databases on an OS (operating system). An application running on the OS is operated as a file on the OS. When an application, such as a database, is operated using a file on the OS, and the application is ended, the file manipulation through the OS is performed using commands provided for the OS. This can cause a command error, which may give rise to the accidental erasing of the file from the OS.
Also, all items of data are integrated into a single data file in the database system, and there are many cases in which various types of accesses, such as data registration, erasing, and the like, can only be made through the database. Such a system in which all items of data are integrated into a single file presents the following problems. In particular, the handling of images, voice, and other information, apart from the text data, makes the amount of data massive, which is thus difficult to handle, thereby resulting in a slowdown in the speeds of retrieval and of other types of processing.
Conventionally, an archive of the type in which a plurality of files are unified or an archive of the type in which files are compressed are available for software for personal computers and work stations. For example, TAR is available for the well-known UNIX (a trademark of UNIX System Laboratories, Inc.). TAR, which is referred to as a tape archive, is largely formed on a tape as a sequentially-accessed auxiliary storage device in such a way that a plurality of items of data are integrated into a single file. TAR can be formed not only on a tape, but also in a file on a hard disk. The archive of this type, which is in the form of a single file, cannot be directly accessed from an application, but requires the procedure of unarchiving and extracting by the user for use.
Further, in the data management apparatus of the foregoing related art, if the file management is commonly performed for the applications and the OS, the files may be accidentally erased by the OS commands through the OS.
Also, most applications, such as databases, are so constructed that all items of data are contained in a single file. Hence, the handling of large-capacity data, such as images and voice, makes the data massive, which is thus difficult to handle.
Moreover, data conversion is required when an item of data which has once been registered is manipulated through the OS other than through the application in which such registration had been performed, thus increasing the burden on the user.